Methods: Twenty-four patients with AIS (Cobb >65°) underwent surgery at a single center between January 2014 and December 2021. The first 10 patients underwent surgery using only IOT (T group), whereas the subsequent 14 patients underwent surgery with a combination of IOT and PO (TP group). Results: The mean preoperative Cobb angles in the T and TP groups were 89.35°±6.05° and 92.32°±9.28°, respectively (p=0.59). The mean flexibility index (FI) of the T and TP groups were 0.31±0.016 and 0.36±0.03, respectively (p=0.41). The mean postoperative Cobb angle in the T and TP groups were 40.25°±5.95° and 19.1°±3.20°, respectively (p=0.041). Apical vertebral rotation improved from mean grade 3.2 (2–4) to grade 2.6 (1–3) in the T group and from mean grade 3.6 (2–4) to mean grade 1.8 (1–3) in the TP group. Postoperatively, the mean thoracic kyphosis was 13.84°±2.10° and 21.02°±1.68° in T and TP groups (p=0.044). Transient signal-loss intraoperatively was noted in two patients, one in each group. No episodes of postoperative neurological deficits were reported. No incidences of pseudarthrosis/implant-related complications were reported at the end of 2 years in either group. Conclusions IOT and PO complement one another and can be safely combined without an attributable risk of neurological injury.

Methods: Twenty-four patients with AIS (Cobb >65°) underwent surgery at a single center between January 2014 and December 2021. The first 10 patients underwent surgery using only IOT (T group), whereas the subsequent 14 patients underwent surgery with a combination of IOT and PO (TP group). Results: The mean preoperative Cobb angles in the T and TP groups were 89.35°±6.05° and 92.32°±9.28°, respectively (p=0.59). The mean flexibility index (FI) of the T and TP groups were 0.31±0.016 and 0.36±0.03, respectively (p=0.41). The mean postoperative Cobb angle in the T and TP groups were 40.25°±5.95° and 19.1°±3.20°, respectively (p=0.041). Apical vertebral rotation improved from mean grade 3.2 (2–4) to grade 2.6 (1–3) in the T group and from mean grade 3.6 (2–4) to mean grade 1.8 (1–3) in the TP group. Postoperatively, the mean thoracic kyphosis was 13.84°±2.10° and 21.02°±1.68° in T and TP groups (p=0.044). Transient signal-loss intraoperatively was noted in two patients, one in each group. No episodes of postoperative neurological deficits were reported. No incidences of pseudarthrosis/implant-related complications were reported at the end of 2 years in either group. Conclusions IOT and PO complement one another and can be safely combined without an attributable risk of neurological injury.

Methods: Twenty-four patients with AIS (Cobb >65°) underwent surgery at a single center between January 2014 and December 2021. The first 10 patients underwent surgery using only IOT (T group), whereas the subsequent 14 patients underwent surgery with a combination of IOT and PO (TP group). Results: The mean preoperative Cobb angles in the T and TP groups were 89.35°±6.05° and 92.32°±9.28°, respectively (p=0.59). The mean flexibility index (FI) of the T and TP groups were 0.31±0.016 and 0.36±0.03, respectively (p=0.41). The mean postoperative Cobb angle in the T and TP groups were 40.25°±5.95° and 19.1°±3.20°, respectively (p=0.041). Apical vertebral rotation improved from mean grade 3.2 (2–4) to grade 2.6 (1–3) in the T group and from mean grade 3.6 (2–4) to mean grade 1.8 (1–3) in the TP group. Postoperatively, the mean thoracic kyphosis was 13.84°±2.10° and 21.02°±1.68° in T and TP groups (p=0.044). Transient signal-loss intraoperatively was noted in two patients, one in each group. No episodes of postoperative neurological deficits were reported. No incidences of pseudarthrosis/implant-related complications were reported at the end of 2 years in either group. Conclusions IOT and PO complement one another and can be safely combined without an attributable risk of neurological injury.